Now, Chrome (and I suspect many other desktop browsers) forgives the // error and displays the page anyway. But some systems are not so forgiving.
For example, see my screenshot of an emailed new topic notification as it appears on my Android mobile. It links only to the root, stopping at the incorrect //.
Can the erroneous duplication be found and weeded out?
maidbloke:
Somewhere in its code the forum is inserting a double slash in the URL.
Fixed.
Let me know if some URL has been broken by the change (it is possible that some forum.arduino.cc/foobar has become forum.arduino.ccfoobar, which is invalid address).